脉冲电沉积工艺参数对Ni-W-P合金镀层性能的影响

针对传统镀硬铬沉积速率低、污染环境等问题,采用脉冲电沉积方法在碳钢表面制备Ni-W-P代铬镀层。采用显微硬度计、扫描电子显微镜、X射线衍射仪和电化学工作站研究了脉冲频率、平均电流密度和占空比对镀层性能的影响。结果表明:随着脉冲频率、平均电流密度和占空比的增加,镀层的硬度和耐蚀性均呈现出先增大后减小的变化规律;当脉冲频率为250Hz,平均电流密度为4.0A/dm2,占空比为30%时,镀层为非晶态结构,表面光滑、平整,结构致密,硬度可达5 140MPa,耐蚀性较好。

Effects of Pulse Electrodeposition Parameters on the Properties of Ni-W-P Alloy Coating

Aiming at the problems of traditional hard chromium plating technology,such as low deposition rate,environmental pollution,etc.,a Ni-W-P coating plated by using pulse electrodeposition method on steel surface was prepared to substitute for chromium coating.Effects of pulse frequency,average current density and duty cycle on the properties of the coating were investigated by microhardness tester,SEM,XRD,and electrochemical workstation.It was found that the hardness and corrosion resistance of the coating increased at first,then decreased with the increasing of pulse frequency,average current density and duty cycle.The results show that the as-deposited coating is of an amorphous structure,of which the surface is smooth,structure compact,corrosion resistance better and the hardness can reach 5 140 MPa when the pulse frequency is 250 Hz,average current density 4.0 A/dm2 and duty cycle 30 %.